#Uniform nanowire arrays for science and manufacturing Defect-free nanowires with diameters in the range of 100 nanometers (nm) hold significant promise for numerous in demand applications including printable
Reproducible synthesis of gallium nitride nanowires with controlled size and location on silicon substrates. The result was achieved by improving selective wire-growth processes to produce one nanowire of controlled diameter per mask-grid opening over a range of diameters from 100 nm to 200 nm.
Ordered arrays with a variety of spacings were fabricated. In the near term the research will be used to create a wafer-scale arrays of probes for devices that examine the surface
and near-surface properties of materials to optimize nanowire LEDS and to produce nanowires with controlled diameter for a collaborative project involving printable transistors for millimeter-wave reconfigurable antennae e
#Designing complex structures beyond the capabilities of conventional lithography Gold nanoparticles smaller than 10 nanometers spontaneously self-organize in entirely new ways
when trapped inside channel-like templates. A new study shows that this feature could facilitate easier nanoscale manufacturing of biosensors and plasmonic devices with intricate high-density surface structures.
Generating surface patterns at scales of 10 nanometers and below is difficult with current technology.
An international team led by Joel Yang from the A*STAR Institute of Materials Research and Engineering in Singapore is helping to circumvent this limitation using a technique known as'directed self-assembly of nanoparticles'(DSA-n). This approach takes spherical nanoparticles that spontaneously organize into ordered two-dimensional films
when inserted into lithographically defined templates. The templates impose geometric constraints that force the films to organize into specific nanoscale patterns.
Most patterns produced by DSA-n however are simple periodic arrangements. To broaden this technique's capabilities researchers are exploring'structure transitions'that occur
when template constraints become comparable to the size of the nanoparticles. At these dimensions the small spheres can dislocate from typical periodic positions
but direct imaging of sub-10-nanometer particles is nearly impossible. That's where we came up with the idea of using templates based on channels with gradually varying widths says co-author Mohamed Asbahi.
With this system we can track the self-assembly of the nanoparticles according to the space accessible to them.
Using electron-beam lithography techniques the team carved out an array of inward tapering trenches designed to fit 1 to 3 rows of gold nanoparticles.
After depositing a monolayer of 8-nanometer particles in the template they used scanning electron microscopy to identify any emergent width-dependent patterns.
Researchers have been using electrodes made up of tiny silicon spheres about 150 nanometers wide#about a thousand times smaller than a human hair#to overcome some of the limitations of silicon as an electrode.
Last year materials scientist Chunmei Ban and her colleagues at the National Renewable energy Laboratory in Golden Colorado and the University of Colorado Boulder found that they could cover silicon nanoparticles with a rubberlike coating made from aluminum glycerol.
Researchers did not know how this coating improved the performance of the silicon nanoparticles. The nanoparticles naturally grow a hard shell of silicon oxide on their surface much like stainless steel forms a protective layer of chromium oxide on its surface.
No one understood if the oxide layer interfered with electrode performance and if so how the rubbery coating improved it.
So Yang He from the University of Pittsburgh explored the coated silicon nanoparticles in action at EMSL.
In the future the researchers would like to develop an easier method of coating the silicon nanoparticles. Explore further:
In situ Transmission Electron microscopy Probing of Native Oxide and Artificial Layers on Silicon Nanoparticles for Lithium ion batteries ACS Nano October 27 2014 DOI:
This innovation in nanotechnology won't soak up enough carbon to solve global warming researchers say. However it will provide an environmentally friendly low-cost way to make nanoporous graphene for use in supercapacitors-devices that can store energy and release it rapidly.
#Nanotubes may restore sight to blind retinas The aging process affects everything from cardiovascular function to memory to sexuality.
Yael Hanein of Tel aviv University's School of Electrical engineering and head of TAU's Center for Nanoscience and Nanotechnology and including researchers from TAU the Hebrew University of Jerusalem and Newcastle University.
The researchers combined semiconductor nanorods and carbon nanotubes to create a wireless light-sensitive flexible film that could potentially replace a damaged retina.
or older who have damage to a specific part of the retina will stand to benefit from the nanotube device
We hope our carbon nanotube and semiconductor nanorod film will serve as a compact replacement for damaged retinas.
We are still far away from actually replacing the damaged retina said Dr. Bareket. But we have demonstrated now that this new material stimulates neurons efficiently and wirelessly with light.
#Nanomaterials to preserve ancient works of art Little would we know about history if it weren't for books and works of art.
In an effort to overcome the limitations of traditional restoration techniques the team has developed promising nanomaterials
This is where the NANOFORART (Nanomaterials for the conservation and preservation of movable and immovable artworks) project comes in.
The three-year project which ends this month has developed advanced nanomaterials for preventive conservation of works of art.
This involved nanomaterials that are physico-chemically compatible with the components of works of art
The advanced nanomaterials we have been working on allow for a more precise control of the restoration intervention for example controlled cleaning can be carried out using microemulsions and chemical hydrogels instead of traditional cleaning methods.
and solutions provided by advanced materials and colloid sciences and more generally nanosciences. These materials are able to resolve degradation issues
The first is the dispersion of calcium hydroxide nanoparticles in short chain alcohols for the consolidation of wall paintings plasters and stone.
The second is the dispersion of alkaline nanoparticles in either short chain alcohols or water for the ph control of movable works of art such as paper parchment and leather.
Dispersions of nanoparticles of calcium hydroxide for the consolidation of wall paintings plasters and stone are already available to conservators worldwide under the trademark Nanorestore.
Nanoparticles for the ph control of movable works of art (e g. paper wood canvas) have been branded under the trademark Nanorestore Paper;
This is the reason why we are proposing a new project within the Horizon 2020 call named NANORESTART (Nanomaterials for the RESTORARTION of the works of modern ART to highlight the new start with respect to classic art conservation) that aims
and if the films were covered with catalytic nanoparticles such as platinum. The discovery makes monolayers of graphene
Lawrence Livermore National Laboratory (LLNL) and The swiss Federal Institute of technology (ETH) researchers have developed a cost-effective and more efficient way to manufacture nanoporous metals over many scales from nanoscale to macroscale
The pattern is transformed in a single polymer mask with nanometer-size features. Last a technique known as anisotropic ion beam milling (IBM) is used to etch through the mask to make an array of holes creating the nanoporous metal.
which is key to creating the unique properties that make nanoporous materials work. The rougher the metal is the less evenly porous it becomes.
One of the biggest problems with this technique is that the metal layer cannot be peeled off uniformly (or at all) at the nanoscale.
because nanoporous materials facilitate anomalous enhancement of transmitted (or reflected light through the tunneling of surface plasmons a feature widely usable by light-emitting devices plasmonic lithography refractive-index-based sensing and all-optical switching.
This ILLO process can enable not only nanoscale processes for high density flexible devices but also the high temperature process that was previously difficult to achieve on plastic substrates.
and substrate a nanoscale process at a high temperature of over 1000c can be utilized for high performance flexible electronics.
The research, published today in Nature Nanotechnology, reports on nuclear pores in frog eggs and reveals how these pores can act like a supercharged sieve,
from the London Centre for Nanotechnology (UCL Mathematics & Physical sciences), said:""The pores have been known to act like a sieve that could hold back sugar
First they made a sandwich composed of two metal electrodes separated by a two-nanometer thick insulating layer (a single nanometer is 10000 times smaller than a human hair) made by using a semiconductor technology called atomic layer deposition.
What is more the recognition tunneling technology we have developed allows us to make a relatively large gap (of two nanometers) compared to the much smaller gaps required previously for tunnel current read-out (which were less than a single nanometer wide.
Specifically when a current is passed through the nanopore as the DNA passes through it causes a spike in the current unique to each chemical base (A c T or G) within the DNA molecule.
while flowing through the two-nanometer gap. The research team is also working on modifying the technique to read other single molecules which could be used in an important technology for drug development.
#Nanoparticles infiltrate kill cancer cells from within Conventional treatment seeks to eradicate cancer cells by drugs and therapy delivered from outside the cell
In contrast to conventional cancer therapy a University of Cincinnati team has developed several novel designs for iron-oxide based nanoparticles that detect diagnose
PTT uses the nanoparticles to focus light-induced heat energy only within the tumor harming no adjacent normal cells.
The UC study used the living cells of mice to successfully test the efficacy of their two-sided nanoparticle designs (one side for cell targeting and the other for treatment delivery) in combination with the PTT.
However the U s. Food and Drug Administration has approved now the use of iron-oxide nanoparticles in humans.
That means the photo-thermal effect of iron-oxide nanoparticles may show in the next decade a strong promise in human cancer therapy likely with localized tumors.
With this technology a low-power laser beam is directed at the tumor where a small amount of magnetic iron-oxide nanoparticles are present either by injecting the particles directly into the tumor
The nanomaterials enter only the abnormal cells illuminating those cells and then doing whatever it is you have designed them to do.
He stated With nanomaterial technology we can detect the tumor early and kill it on sight at the same time.
Scientists identify this certain biomarker that is specific to a certain tumor then conjugates this biomarker on the surface of the nanocarrier that only has the expression for that specific kind of cancer cell.
The nanotech carriers go into the body through a vein in the blood stream seek the abnormal cancer cells find the biomarker
The laser light heats the nanoparticles to at least 43 degrees Celsius to kill the cancer cells ultimately leaving all the other cells in the body unharmed.
Future research in nanoparticle PTT will look at toxicity biodegradability and compatibility issues. Shi said that the team is currently looking for other diverse biodegradable materials to use for the carriers such as plant chlorophylls like those in cabbage that are both edible and photothermal.
We have created possibly the smallest-ever stereoscopic images using pixels formed from plasmonic nanostructures Yang told Phys. org.
metal nanostructures can scatter different wavelengths (colors) of light due to the fact that the tiny nanostructures themselves resonate at different wavelengths.
If a nanostructure is circular its resonance is polarization-independent because the diameter of the circle is the same from all directions.
However if a nanostructure is biaxial (such as an ellipse or rectangle) its resonance will depend on the polarization of the incident light.
To do this the researchers created nanopixels out of tiny pieces of aluminum a hundred or so nanometers across.
For example nanostructures that have circularly asymmetric shapes could have more than two polarization-dependent resonances due to the additional circularly polarized dimension.
NTU associate professors Zhang Qichun and Joachim Loo have found a way to make the nanoparticle light up
The breakthrough has resulted in two papers published in Small one of the world's top scientific journals for material science and nanotechnology.
Prof Loo said their new biomarker can#also release anticancer drugs by creating a layer of coating loaded with drugs on the outside of the nanoparticle.#
and potentially target the delivery of drugs at the same time as proven in small animal tests said Prof Loo a nanotechnology and bioimaging expert.
Our breakthrough will open up new doors in the various fields of nanomedicine bioimaging and cancer therapeutics.
Inorganic#Organic Hybrid Nanoprobe for NIR-Excited Imaging of Hydrogen sulfide in Cell Cultures and Inflammation in a Mouse Model.
#A gut reaction Queen's university biologist Virginia Walker and Queen's SARC Awarded Postdoctoral Fellow Pranab Das have shown nanosilver
The discovery is important as people are being exposed to nanoparticles every day. Nanosilver is used also in biomedical applications toys sunscreen cosmetics clothing and other items.
We were surprised to see significant upset of the human gut community at the lowest concentration of nanosilver in this study says Dr. Das.
To our knowledge this is the first time anyone has looked at this. It is important as we are exposed more and more to nanoparticles in our everyday lives through different routes such as inhalation direct contact or ingestion.
To conduct the research Drs. Walker and Das utilized another Queen's discovery repoopulate created by Elaine Petrof (Medicine.
In this instance rather than being used as therapy the synthetic stool was used to examine the impact of nanoparticles on the human gut.
The research showed that the addition of nanosilver reduced metabolic activity in the synthetic stool sample perturbed fatty acids
This information can help lead to an understanding of how nanoparticles could impact our gut ecosystem.
There is no doubt that the nanosilver shifted the bacterial community but the impact of nanosilver ingestion on our long-term health is currently unknown Dr. Walker says.
This is another area of research we need to explore. The findings by Drs. Das and Walker Julie AK Mcdonald (Kingston General Hospital) Dr. Petrof (KGH) and Emma Allen-Vercoe (University of Guelph) were published in the Journal of Nanomedicine and Nanotechnology.
Explore further: Building materials may impact Arctic tundra More information: omicsonline. org/open-access/na#157-7439.1000235. pd
Silver nanowire ink which is highly conductive and stable offers a more practical solution. Hu's team wanted to develop a way to print it directly on paper to make a sensor that could respond to touch or specific molecules such as glucose.
Direct Writing on Paper of Foldable Capacitive Touch Pads with Silver nanowire Inks ACS Appl. Mater.
10.1021/am506987w Abstractpaper-based capacitive touch pads can be fabricated utilizing high-concentration silver nanowire inks needle-printed directly onto paper substrates through a 2d programmable platform.
Post deposition silver nanowire tracks can be sintered photonically using a camera flash to reduce sheet resistance similar to thermal sintering approaches.
Touch pad sensors on a variety of paper substrates can be achieved with optimized silver nanowire tracks.
#Study suggests light may be skewing lab tests on nanoparticles'health effects Truth shines a light into dark places.
That's what recent findings at the National Institute of Standards and Technology (NIST) show about methods for testing the safety of nanoparticles.
It turns out that previous tests indicating that some nanoparticles can damage our DNA may have been skewed by inadvertent light exposure in the lab. Nanoparticles made of titanium dioxide are a common ingredient in paint
scientists have accepted long that these nanoparticles would not damage cells by forming free radicals from light activation.
whether light was required indeed for the nanoparticles to cause DNA damage.""We didn't set out to test the safety of the particles themselveshat's for someone else to determine,
"The NIST team exposed samples of DNA to titanium dioxide nanoparticles under three different conditions: Some samples were exposed in the presence of visible
"The results suggest that titanium dioxide nanoparticles do not damage DNA when kept in the dark,
must be controlled carefully before drawing conclusions about nanoparticle effects on DNA
#Research team developing injectable treatment for soldiers wounded in battle Internal bleeding is a leading cause of death on the battlefield,
By inserting two-dimensional nanoplatelets into the hydrogel, the team was able to tweak the mechanical properties of material.
Two-dimensional materials are ultrathin substances with high surface area but a thickness of a few nanometers or less.
For example, a sheet of paper is 100,000 nanometers thick; Gaharwar's nanoplatelets are one nanometer thick. Gaharwar and his colleagues employ two-dimensional, disc-shaped particles known as synthetic silicate nanoplatelets.
Because of their shape, these platelets have a high surface area, he explains. The structure, composition and arrangement of the platelets result in both positive and negative charges on each particle.
These charges, Gaharwar explains, cause the platelets to interact with the hydrogel in a unique way.
these disc-shaped nanoplatelets interact with blood to promote clotting, Gaharwar says, noting that animal models have shown clot formation occurring in about one minute as opposed to five minutes without the presence of these nanoparticles.
Animal model, he adds, also have demonstrated the formation of lifesaving clot formations when the enhanced biomaterial was used."
"These 2d, silicate nanoparticles are unprecedented in the biomedical field, and their use promises to lead to both conceptual and therapeutic advances in the important and emerging field of tissue engineering, drug delivery, cancer therapies and immune engineering,
#Quantum dot technology makes LCD TVS more colorful energy-efficient If LCD TVS start getting much more colorful and energy-efficient in the next few years,
it will probably be thanks to MIT spinout QD Vision, a pioneer of quantum dot television displays.
Quantum dots are light-emitting semiconductor nanocrystals that can be tuned by changing their size, nanometer by nanometer to emit all colors across the visible spectrum.
By tuning these dots to red and green, and using a blue backlight to energize them,
Last June, Sony used QD Vision product, called Color IQ, in millions of its Bravia riluminostelevisions, marking the first-ever commercial quantum dot display.
and others developed a pioneering technique for producing quantum dot LEDS (QLEDS). To do so, they sandwiched a layer of quantum dots, a few nanometers thick, between two organic thin films.
When electrically charged, the dots illuminated a light bulb 25 times more efficiently than traditional devices.
became a landmark in the quantum dot-devices field. oon venture capitalists were calling Vladimir, asking if we spin a company out,
quantum dot displays. aking a transition like that from lighting to displays tests the nerves of folks involved, from top to bottom,
and last year became the first to market with a quantum dot display. Today, QD Vision remains one of only two quantum dot display companies that have seen their products go to market.
Now, with a sharp rise in commercial use, quantum dot technologies are positioned to penetrate the display industry
Coe-Sullivan says. Along with Color IQ-powered LCD TVS, Amazon released a quantum dot Kindle last year,
and Asus has a quantum dot notebook. nd there nothing in between that quantum dots can address,
he says. In the future, Coe-Sullivan adds, QD Vision may even go back and tackle its first challenge:
and value proposition for quantum dot lighting. n
#Streamlining thin film processing saves time energy Energy storage devices and computer screens may seem worlds apart but they're not.
and the biochar nanoparticles can create an extremely large surface area which can then hold more charge.
The high-energy plasma can deposit highly transparent and conductive thin films create high quality semiconductors and pattern micro-or nanoscale devices thus making the display images brighter and clearer.
#New nanocomposites for aerospace and automotive industries The Center for Research in Advanced Materials (CIMAV) has developed reinforced graphite nanoplatelets seeking to improve the performance of solar cell materials.
These polymer-based nanocomposites are reinforced with graphite nanoplatelets for use in industry. Nanocomposites are formed by two
or more phases in this case by reinforced graphite nanoplatelets. The sectors focused on the use of these nanomaterials are diverse;
nanoplatelets impart new properties to materials; this allows us to move into the automotive construction aerospace textile and electronics sectors
which are demanding and where the use of nanomaterials is an opportunity explains Licea Jimenez.
According to the specialist at CIMAV the research is applied already in some concept testing for mechanical and thermal modification in the construction industry.
Additionally nanocomposite materials are used already in fenders and panels in the automotive and textile industry.
The development of nanocomposites in this research center is an opportunity for different industry sectors; graphite nanoplatelets give added value to the product as they improve its mechanical thermal and electrical properties.
And they have an impact on the industry because the business demands are increasing and the use of nanocomposites is an opportunity to improve the product.
Even some of the companies we have worked with mentioned in several forums that they have had a good response in the use of these nanomaterials.
She also affirms that the nanocomposites Laboratory in Monterey has achieved success but recognizes that they need to engage with sectors such as aeronautics among other areas.
Jimenez Licea indicates that in addition to companies in the northern state of Nuevo Leon there are companies in other states that have shown interest in polymer nanocomposites;
It is an advantage to work with research projects demanded by the industry because they have a specific function for each company.
This is because each nanocomposite is a material that has two or more constituents in this case the polymer and a nano-sized reinforcing material:
the graphite nanoplatelets s
#Graphene/nanotube hybrid benefits flexible solar cells Rice university scientists have invented a novel cathode that may make cheap, flexible dye-sensitized solar cells practical.
The Rice lab of materials scientist Jun Lou created the new cathode, one of the two electrodes in batteries,
from nanotubes that are bonded seamlessly to graphene and replaces the expensive and brittle platinum-based materials often used in earlier versions.
The discovery was reported online in the Royal Society of Chemistry's Journal of Materials Chemistry A. Dye-sensitized solar cells have been in development
"The breakthrough extends a stream of nanotechnology research at Rice that began with chemist Robert Hauge's 2009 invention of a"flying carpet"technique to grow very long bundles of aligned carbon nanotubes.
In his process, the nanotubes remained attached to the surface substrate but pushed the catalyst up as they grew.
The graphene/nanotube hybrid came along two years ago. Dubbed"James'bond"in honor of its inventor, Rice chemist James Tour, the hybrid features a seamless transition from graphene to nanotube.
The graphene base is grown via chemical vapor deposition and a catalyst is arranged in a pattern on top.
which lifts off and allows the new nanotubes to grow. When the nanotubes stop growing,
the remaining catalyst (the"carpet")acts as a cap and keeps the nanotubes from tangling.
The hybrid material solves two issues that have held back commercial application of dye-sensitized solar cells,
First, the graphene and nanotubes are grown directly onto the nickel substrate that serves as an electrode,
With no interruption in the atomic bonds between nanotubes and graphene, the material's entire area, inside and out, becomes one large surface.
Lou's lab built and tested solar cells with nanotube forests of varying lengths The shortest,
Other nanotube samples were grown for an hour and measured about 100-150 microns. When combined with an iodide salt-based electrolyte and an anode of flexible indium tin oxide,
Tests found that solar cells made from the longest nanotubes produced the best results and topped out at nearly 18 milliamps of current per square centimeter
"We're demonstrating all these carbon nanostructures can be used in real applications, "he said
#Bio-inspired bleeding control: Researchers synthesize platelet-like nanoparticles that can do more than clot blood (Phys. org) Stanching the free flow of blood from an injury remains a holy grail of clinical medicine.
Controlling blood flow is a primary concern and first line of defense for patients and medical staff in many situations from traumatic injury to illness to surgery.
By creating nanoparticles that mimic the shape flexibility and surface biology of the body's own platelets they are able to accelerate natural healing processes
That's where platelet-like nanoparticles (PLNS) come in. These tiny platelet-shaped particles that behave just like their human counterparts can be added to the blood flow to supply
According to Anselmo's investigations for the same surface properties and shape nanoscale particles can perform even better than micron-size platelets.
and wound healing in older patients by using nanoparticles that can target where clots are forming without triggering unwanted bleeding.
In other applications bloodborne pathogens and other infectious agents could be minimized with antibiotic-carrying nanoparticles.
#Engineers efficiently'mix'light at the nanoscale The race to make computer components smaller and faster
Researchers at the University of Pennsylvania have engineered a nanowire system that could pave the way for this ability,
the researchers needed a way to amplify the intensity of a light wave as it passed through a cadmium sulfide nanowire.
partially wrapping the nanowire in a silver shell that acts like an echo chamber. Agarwal's group had employed a similar design before in an effort to create photonic devices that could switch on and off very rapidly.
but, by changing the polarization of the light as it entered the nanowire, the researchers were able to better confine it to the frequency-altering, nonlinear part of the device:
the nanowire core.""By engineering the structure so that light is contained mostly within the cadmium sulfide rather than at the interface between it and the silver shell,
which can be done by altering the size of the nanowire and the shell.""Most important,
however, was that this frequency mixing was possible on the nanoscale with very high efficiency.
and push the device size into the nanoscale. c
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